Personal page Indre Urbanaviciute

I am a PhD student at Complex Materials and Devices group, supervised by Martijn Kemerink.

I defended my bachelor (in physics, 2013) and master (in material science, 2015) theses at the Department of Solid-state Electronics, Vilnius University, Lithuania. My research covered the investigation of charge transport, photoluminescence and electroluminescence properties of new small molecular weight organic molecules [1] and the production of white and coloured multilayer OLEDs using them as an emissive layer [2].

Here in the CoMaDe group I have turned my interests from organic semiconductors to molecules that contain switchable electric dipole groups – ferroelectric polymers, oligomers and discotic columnar liquid crystals. A highly ordered arrangement of molecules with respect of each other is essential for the formation of a macro-dipole and thus for ferroelectric activity, see Figure 1. In order to achieve this functionality, the molecular structure must therefore not only contain dipolar moieties but also facilitate long-range ordering.

Collaboration with organic chemists has opened wide possibilities to study series of new ferroelectric compounds. After thorough exploration of the morphological and ferroelectric properties (e.g. see Figure 2) we are able to obtain precious information about structural influences on the performance of ferroelectric devices. There is wide variety of devices taking advantage of functionality of ferroelectric materials, for example thin-film transistors, resistive memory diodes, batteries, various sensors and solar cells, not to mention variable capacitors or ferroelectric memories. And this is not even taking into account possible piezoelectricity and pyroelectricity!

The organic origin of the materials under scope assures potentially easy and cheap device fabrication, low processing temperatures and mechanical flexibility. Naturally, it also brings new problems, which we will try to overcome during this PhD project and, hopefully, we will be able to harness new ferroelectric materials that add novel functionality to organic electronics

Figure 1. Appearance of electrical macro-dipole caused by alignment of discotic columnar liquid crystals. On the right a typical example, BTAs [3].